Apparatus for converting continuous motioninto interrupted motion



March 30, 1937. 2,075,103

APPARATUS FOR CONVERTING CONTINUOUS MOTION INTO INTERRUPTED MOTION P. G.EDWARDS ET AL Filed July 18, 1935 INVENTORS B GZdwardsfl BYEFSlw/ ZSZQZZATTORNEY Patented Mar. 30, 1937 PATENT OFFICE APPARATUS FOR CONVERTINGCONTINU- OUS MOTION TION INTO INTERRUPTED MO- Paul Griffith Edwards,Verona, and Hugh Franklin Shoffstall, Maplewood, N. J., assignors toAmerican Telephone and Telegraph Company, a corporation of New YorkApplication July 18, 1935, Serial No. 32,074

2 Claims.

This invention relates to arrangements for changing continuous motioninto interrupted motion. More particularly, this invention relates toarrangements for converting continuous rotary motion into discontinuousrotary motion. Still more particularly, this invention relates toarrangements for the conversion of random rotary or oscillatory motioninto motion which varies in finite and discrete steps.

When viewed from a different angle, this invention relates toarrangements for converting the motion of a device which continuouslyvaries in accordance with, for example, the temperature of some deviceor apparatus, or with the resistance or gain of a circuit into othermotion which may correspond to the variable motion but which will varyonly in finite or discrete steps.

It is contemplated that this arrangement is applicable to numerousinstances involving for example, the control of the gain of a telephonerepeater from the resistance of a pilot wire in order to compensate forchanges in loss of the associated line due to temperature. The inventionis also applicable to compensate for changes in gain and frequencycharacteristics of carrier circuits under control of a pilot channel orthe like.

This invention will be better understood from the detailed descriptionhereinafter following, when read in connection with the accompanyingdrawing, which illustrates one embodiment of the invention.

Referring to the drawing, the reference character I designates a drivingshaft which may be associated with apparatus having a characteristic,let us say, of temperature, pressure, resistance, gain or other propertywhich may continuously change. In other words, the driving shaft I mayrotate and carry its arm 1 between two switchhooks 2 and 3 which may bespaced from each other by some predetermined distance. The arm I mayunder normal conditions be equally spaced from the switchhooks 2 and 3or it may, under the action of the apparatus which controls the drivingshaft I, assume some other position between these switchhooks. When thecharacteristic of the apparatus which determines the rotation of thedriving shaft l is such that the arm I is moved through a largerdistance, either of the switchhooks 2 or 3 may then be movedsufficiently to close the corresponding contacts 2' or 3'. Thus if thedriving shaft is rotated in a clockwise direction and the torque issufiicient to have the arm I strike contact 3, the switchhook 3 willthen close contact 3. On the other hand,

if the torque on the driving shaft l is in a counterclockwise direction,the arm I may be caused to contact switchhook 2 and thereby closecontact 2.

The reference character 4 designates a shaft which is intended to bedriven in a direction which corresponds to the direction of rotation ofthe driving shaft I. There are two ratchet wheels 5 and 6 which arekeyed to the driven shaft 4. These ratchet wheels may be rotated underthe control of two pawls, I and 8, both of which are normally spacedfrom the teeth of the ratchet wheels. In order to produce the necessaryspacing of these pawls from the corresponding ratchet devices, springs 9and ID are employed. The pawls I and 8 may be made of iron or othermagnetic material in order that they may be attracted by theelectromagnetic fields produced by electrical windings, as will bepointed out hereinafter.

A battery orother source of current is designated ll. One terminal ofthis source is connected to'both of the switchhooks 2 and 3. The otherterminal of the source is connected to one of the terminals ofelectrical windings l2 and I3 which control the movement of thecorresponding pawls 'l and 8. The other terminal of the winding [2 isconnected to the contact 3' and the second terminal of the winding I3 isconnected to the contact 2'.

The switchhooks 2 and 3 are normally insulated from the correspondingcontacts 2 and 3. These switchhooks and associated contacts are allmounted upon the shaft 4 so that any movement of the shaft 4 will changethe relative positions of both of the switchhooks with respect to thearm I. In other words, if the shaft 4 is rotated in a clockwisedirection, both of the switchhooks 2 and 3 will also be rotated in aclockwise direction for a corresponding angular distance and will carrythe corresponding contacts 2' and 3' along with them.

The operation of the arrangement shown in the drawing is as follows:

When the driving shaft l is rotated in a counter clockwise direction,the shaft 4 will remain stationary until the arm I is brought intocontact with the switchhook 2. When this happens the contact 2 will beclosed by the switchhook 2 and a circuit will be established from thesource or battery ll through the winding of the electromagnetic deviceI3. The device l3 will be energized by the flow of current therethroughand the electromagnetic field established thereby will be sufficient toattract the pawl 8 against the tension of the spring In. As the pawl 8is moved downwardly in the direction of the wind- 7 tact 2'.

' ing I2.

ing I3, it will engage the ratchet wheel 6 and rotate the ratchet wheelone step in a counter clockwise direction. Thus, the distance throughwhich the ratchet wheel 6 is rotated will be no more than the spacingbetween any two of its adjacent teeth. When the ratchet wheel 6 rotatesin a counter clockwise direction, it will carry with it the shaft 4 uponwhich it is mounted. The rotation of the shaft 4 in a counter clockwisedirection will also carry with it the device which supports theswitchhooks 2 and 3. Thus the switchhook 2, which was formerly closed bythe arm I, will be separated from the arm I and thereby open the circuitof the winding I3 at the con- In other words, after the shaft 4 hasrotated through a small angular distance, the current formerly suppliedby the source II to the winding of the elctromagnetic device I3, will beinterrupted.

If the driving shaft I is further rotated in the same direction, that iscounter clockwise, the arm I may again be moved sufficiently so as tocontact the switchhook 2, The circuit of the winding I3 will be closedat contact 2 and the same operation will be repeated causing therotation in a counter clockwise direction of the ratchet wheel 5 and theshaft 4 upon which it is mounted, as well as the device which supportsthe switchhooks 2 and 3.

If the driving shaft I is moved in a clockwise direction by a torquewhich is suificient to move the arm I into contact with the switchhook3, the contact 3 will then be closed and current will then flow from thesource II through the wind- The electromagnetic field produced by thewinding I2 will attract the pawl I against the tension of the spring 9and it will engage one of the teeth of the ratchet wheel 5, causing thisratchet wheel to move in a clockwise direction and carry with it theshaft 4. The shaft 4 will also carry the device upon which theswitchhooks 2 and 3 are mounted and therefore the switchhook 3 will beseparated from the arm I and the contact 3 will be opened. Just as soon7 as the contact 3 is opened, the current from the source II flowingthrough the winding I2 will be interrupted and the shaft 4 will thenbecome stationary. Unless the torque on the driving shaft I issufficient to cause the arm I to contact the switchhook 3, no currentwill flow from the source II through the winding I2.

So it will be seen that the continuously rotating or oscillating drivingshaft I is caused to rotate the shaft 4 in a corresponding direction,that is, clockwise or counter clockwise, but the continuous rotation ofthe shaft I will be responsible for discontinuous rotation of the shaft4. In other words, the continuous rotation of the shaft I will producerotation of the shaft 4 in finite or discrete steps.

While the ratchet wheels 5 and 6 have been shown mounted upon a commonshaft, separate and independent shafts, properly coupled to each otherby gears, sprockets or the like, and coupled to the switching means maybe employed. When so arranged, one of these shafts will only rotate inone direction and the other shaft will only rotate in the oppositedirection. Moreover, the ratchet wheels may be replaced by any toothedor other stepping devices.

While the driving shaft I and the driven shaft 4 have been shown anddescribed as being in alignment, such an arrangement is not essential.These shafts may be parallel, but not aligned with each other or theymay make an angle with each other. Such an arrangement may beparticularly desired where the driving shaft rotates only through somepredetermined angle as, for example 150.

It will be understood also that the driving shaft I and the arm I may bethe moving element of any instrument such as an ammeter, voltmeter orthe like and that the closure of either of the associated contacts orswitchhooks 2 or 3 will control the driven shaft 4 which in turn maycontrol a circuit or other apparatus.

While this invention has been shown and described in certain particulararrangements merely for the purpose of illustration, it will beunderstood that the general principles of this invention may be appliedto many and widely varied organizations, without departing from thespirit of the invention and the scope of the appended claims.

What is claimed is:

1. Apparatus for converting the motion of a continuously rotating shaftinto interrupted motion of another shaft mechanically coupled to thecontinuously rotating shaft comprising two toothed wheels mounted uponthe driven shaft, means including a resilient switching device mountedupon and carried by the driven shaft and a circuit controlled by saiddevice and responsive to the rotation of the driving shaft in onedirection to rotate one of the toothed wheels step by step in onedirection, and means including another resilient switching devicemounted upon and carried by said driven shaft and a circuit controlledby the latter device and responsive to the rotation of the driving shaftin the other direction to rotate the other toothed wheel step by step inthe opposite direction.

2. The combination of a driving shaft, an arm carried by the drivingshaft and out of alignment therewith, a driven shaft, two toothed wheelsmounted concentrically about the driven shaft, two flexible switchhookssupported and carried by the driven shaft and spaced on opposite sidesof the arm of the driving shaft, each switchhook being flexed whenengaged by said arm, two electromagnetic devices each operativelyassociated with one of the switchhooks when the switchhook is flexed,and means for coupling each of the electromagnetic devices with one ofthe toothed wheels to control its rotation.

PAUL GRIFFITH EDWARDS. HUGH FRANKLIN SHOFFSTALL.

